Conduit.



PATENTED JUNE 4', 1907.

G. RUSSELL.

GONDUIT.

APPLIOATION FILED AUG. 22. 1906.

IfIVENTOR conduits as are these conduits process, or

tion of the wire.

form of a conduit having p my invention Allegheny and l set f orth.. ,and described and chosen RUSSELL, or MCKEESPORT, PENNSYLVANLA:

CON DulT.A

Application filed August 22,

Speciicaton of Letters Patent.

'resented June 4,1967.

1906. Serial No. 331,661.

To all, wftom `it may concern;

Be it known that I, GEORGE RUSSELL, at resident of McKeesport, in the county of State of Pennsylvania, have invented a new and useful Improvement in Conduite; and I do hereby declare the f ollowing to be a full, clear, and exact descripl.

like partsm relates to-conduits for election thereof.

My invention tric wires, and has special reference to such formed Jr'iom metal tubing and provided with coatings 'to form smooth surfaces. Heretofore, in t e manufacture of the tube was required to be subjected toa pickling and a sand-blasting tosome other process, in order to rovide the same with smooth surfaces and thereby overcome all liability of stripping the insulation off the wires inthe running ofthe samethrou h the conduits. These ickand .sand-blasting rocesses were abo- .rious and expensive an -bothwould have a tendency to weaken the pipe or tube to a great extent, while the acid used in ickling. would also render thepip'e or tube iable to become' rusted and thereby spoil the same for the purpose intended. It also attacksthe threads on pipe and coupling thus' making it almost impossible to get anabsolutely, tight joint, and unless great care is exercised to remove all tracesl of the acid there is dange of it attacking and weakening the insula- The object `of my invention isto do away with these pickling and sand-blastinghprocesses, thus ermitting the use of a` 'ghter -weight stoc for the pipe time' provide a cheap,

and at the same simple and elicient the smooth surface reti/[nir y invention consists, generally stated, in

`the arrangement', construction and combination of parts, -as hereinafter more specifically particularly pointed out yin the claims',

To enable others skilled'in the art to which invention` a pertains to construct and use my im rove conduitj'for electric wires, I will descri the same more fully, referring to the accompan drawing, in whichi Figure '1 is a si e elevation partly section of a section of metalxpipe or tubiig showing ap li thereto. 1g. 2 is a cross-section of t e tube. Fig. 3 is. an end view of the same. Fig. 4i is a side elevation ranged as to width that they showing another lining 2 is tubular inf manner yit is -rolled up ,held in. this positionit is inserted partly'in section of a tube section Showing another manner ofv carrying out the invention.` Fig. '5 is an showing it ready to be insertedinto the tubing.' Fig. 6 is a cross-section of the conduit form of the lining..

of reference herein indicateA -Like symbols yeach of the iigures of thev draw-` ing. v

As illustrated in the drawing, 1 represents a piece of metal tubing for'forming the conduit which is usually of iron or steel, and within'such tubing is placed a lining 2. This orm and is made from a thin and iiexible sheet metal plate 3 having Aaninsulating coating 4 of enamel on the face thereof which forms t surface of the lining, and such coating isv of any suitable flexible enamel composition like that used in the manufacture of ferroty e plates, which is in the beapplied to the plateand then baked intothe same in any suitable -manner of heating. After the late3 has been cut in the proper width and eii'gth and coated in the above into a tubular form` and tosize smaller .than the interior of'the tubing 1, as shown in Fig.- 5, and while being into and run through the -said tubing ,to its proper. posi-v tion so that when it is released it will spring out against the interior Wall I of said tubing and yiorm the lining 2 with the coated face 4 thereon forming the interior surface of said conduit. When the lining 2 is thus in place, the protruding ends of the same are bent 'or iianged back against the ends ofthe tubing 1 as shown at '5, andthe side edges 6 of the end view of the lining referably i e interior plate 3 in forming such lining 2.are so arwill about meet or s ightly overlap each other when the lining isin lace within said tub' p If it is desired, the side e Ges of the plate 3` can be angedpbackat opposite positions to each other, as shownat 7 in Fig. 6, sc that when such plate is rolled up and isdnserted into the tubing 1, the iianges 7 will interlock with each other when the plate is sprung out against said tubing therein. It will also be evident that t e metallic plate 3" need not be 'coated with' the iiexible enamel composition at the time it .is placed within'the tubing 1v but' such compo` sition can be ap lied to the same after the metallic lining 2 is inserted andsecured withand so form a lapl-)oint IOO the dipping of the conduit Will also be enabled to runA along the side edges 6 of the lining and thereby form a tight joint and between the tubing and lining as Well as under the flanges in order to further protect land' insulate the conduit.

Various other modiiications and changes in the construction, design and manner of forming my improved conduit may be resorted to Without departing from the spirit of the in- .vention or sacrificing any of its advantages.

, It Will thus be seen that in my improved' conduit for electric Wires there is provided a cheap and simple method of obtaining a tubing With a non-metallic coating thereon, and

such coating on the interior of a metallic lining within such tubing will form a smooth polished surface for fishing the Wires through the conduit and for preventing all liability of injury to the insulation. on such Wires, While at 4the same Atime such coatings on the interio'r, exterior, and between the tubing and lining'will act as an insulator.

lI am aware that it has been proposed that a metal tubing can be .provided With an exterior and interior coating of zinc through an electrolytic, process or electro galvanizing and that such electrogalvanized tubing is provided with an interior coating of iiexible material on said zinc coating.

I am also aware that a structure composed of a thin metallic pipe and having its vinterior galvanized and its exterior lunited to a comdipping the latter into the same or by placin the` pipe in a mold and pouring the materia therein, but- What I claim as my invention and desire to secure by Letters Patent is: f'

l. A conduit for electric Wires comprising a metal ipe having a ilexible metallic lining Within t e same and a flexible enamel` coating on the inner surface of said lining. V

2. A conduit for electric Wires comprising a metal pipe having a thin flexiblel sheet metal lining Within the same and a flexible enamel coating on the innersurface of said lining. i

3. -A yconduit for electric Wires comprising a' metallpipe having a lexible secured Within the same and a flexible, enamel position. covering placed upon the pipe by` coating on the inner surface of said lining.

4. A conduit for electric Wires comprising a metal pipe having a metal lining secured Within thel same and a flexible enamel coating on the inner surface of said lining. l

In testimony RUSSELL have hereunto set my hand. GEORGE RUSSELL.

' Witnesses:

JAMES L. Wann, WM. R. MoCoMMoN.

metallic lining .iiexible sheet-j whereof, Ithe said GEORGE 

